Days Sales Outstanding (DSO) Calculator
Calculate Days Sales Outstanding (DSO), the average number of days it takes to collect payment after a sale. A lower DSO means faster cash collection and better accounts receivable management.
How to use this tool
- Enter average accounts receivable, net credit sales (revenue) and period length in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your days sales outstanding and the full breakdown beneath it.
⚠ This tool provides general estimates for education only and is not financial, tax or legal advice. Figures may not reflect your situation — verify with a qualified professional.
Formula
DSO = (Average Accounts Receivable ÷ Net Credit Sales) × Number of Days
Equivalently: DSO = Days ÷ AR Turnover Ratio, where AR Turnover = Revenue ÷ Average Accounts Receivable.
How it works
Days Sales Outstanding measures the average number of days that elapse between making a credit sale and receiving payment. It is a core component of the Cash Conversion Cycle (CCC = DIO + DSO − DPO). A lower DSO indicates that a company collects receivables quickly, reducing the risk of bad debts and improving working capital. Industry benchmarks vary considerably; B2B companies often target DSO below 45 days.
Worked example
Software Company Receivables Analysis
- A software company has average accounts receivable of $60,000 and annual net credit sales of $400,000 over 365 days.
- Apply the formula: DSO = (AR ÷ Revenue) × Days = (60,000 ÷ 400,000) × 365.
- Fraction: 60,000 ÷ 400,000 = 0.15.
- Multiply: 0.15 × 365 = 54.75 days.
The DSO is 54.75 days, meaning the company takes about 55 days on average to collect payment after a sale.
Common mistakes to avoid
- Including cash sales in the revenue denominator rather than credit sales only, artificially lowering DSO and understating collection risk.
- Using ending accounts receivable rather than average AR (beginning + ending / 2), distorting DSO in periods with seasonal sales patterns.
- Benchmarking DSO against a flat 30-day target without considering stated payment terms -- if terms are net 60, a 55-day DSO indicates excellent collection performance.
Key terms
- What does DSO measure?
- DSO measures the average number of days a company takes to collect payment from customers after a credit sale is made.
- What is a good DSO?
- A DSO lower than your payment terms (e.g., net 30) is ideal. Many analysts flag DSO above 45 days as a potential collection concern, though norms vary by industry.
- Should I use total sales or only credit sales?
- Only net credit sales should be used, since cash sales generate no receivables. Using total sales understates DSO for businesses with significant cash transactions.
- How can a company reduce its DSO?
- Companies can reduce DSO by tightening credit policies, offering early payment discounts, improving invoicing speed, and following up on overdue accounts promptly.
Frequently asked questions
- What is a good DSO for a B2B business?
- DSO should generally be close to stated payment terms. If you offer net 30, a DSO of 35-40 days is reasonable; above 50 days suggests collection problems. Construction and government contracting routinely see 60-90 day DSO due to industry norms.
- How does DSO affect cash flow?
- Every day of DSO represents one day of average daily sales tied up in receivables. Reducing DSO by 5 days on $10M annual revenue frees approximately $137K in cash. DSO management is a critical lever for capital-intensive businesses.
- How is DSO different from debtor days?
- They are the same metric. DSO is the U.S. accounting term; debtor days is the equivalent used in UK and Commonwealth financial reporting.